Under the recently rewritten Renewable Energy Sources Act (Erneubare-Energien-Gesetz; EEG), which became law on April 1, 2000 in the German Parliament, electricity originating from photovoltaic systems which is then fed into the grid (Grid Coupling) must be compensated for by the grid operators at a minimum cost of $ 0.50 / kWh. In addition, the German Federal Government will subsidise about 36 % of the costs of installing photovoltaic systems according to the 100,000 Solar Roofs Programme (100.000 Dächer-Solarstrom-Programm). The cost of production of current in Germany is around $ 0.88 / kWh per 15 years of use up to repayment of capital investment.